DUAL Brake Master Cylinders

Can someone help me to understand how an IH Metro brake system with two brake master cylinders works? I cannot find any information on them at all. Chassis is a 1956. Thank you in advance for any help!! Keven

Keven, If at all possible, could you post pictures of the items you are asking about. I know that some of the folks are "visual" oriented people like I am. It helps to see it.

Thank you, I would love to but the parts are missing. The previous owner removed them, when I asked how the system worked he gave this photo ant the Pn for the cylinders, but nothing else.

I realize that these are on American made trucks, but they are essentially the same. The CTS-2000 International "S" Line Service Manual for Models built 1956-1957 (Used Silver Diamond and Black Diamond BD-220, 241, 264 and 269, 282 308 engines. (794 pgs), reprint. $74.95
And the MT-102 International AB, AM, CM, SA, & SM Models Metro Truck Parts Catalog, (792 pgs) reprint. $71.95

Might be two good resources for parts and information, They are available at https://www.binderbooks.com/1950-57,%20 ... Trucks.htm

There do not seem to be a lot of Metro owners out there, and any resources like these books are good to have if you are really wanting to put it back together. You can also look to see if someone has them for sale on ebay.

Here is one that ends today in Canada: https://www.ebay.com/itm/vintage-intern ... Tf&vxp=mtr and it is real reasonable!

The only two "duel master" things I know of are:
1: a side by side duel master for brake and clutch, each a single line output, but that is not what you have because I think I see a mechanical clutch linkage.
2: a single master cyl with a frame mounted Hydrovac. Some seam to think a hydrovac is a 2nd master, but it is not, it is a slave operated booster.
Do either of these sound like what you want info on?
Then of course there is the tandem master with two output lines for a split (front/rear) system.